System of electrical distribution



L. A. WATSON.

SYSTEM 0F ELECTRICAL DISTRIBUTION.

APPLIcATxoN FILED sEP. 1,9. 1919.

1,389,329. Patentedmg. 30,1921.

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'MWL UNITED STATES yra'laN'r foFFlcE.

LEONARD A. WATSON, OF BROOKLYN, NE'W YORK, ASSIGNOR TO THE SAITY GAR HEATING .AND LIGHTING COMPANY, 0F NEW YORK, 'Nr Y., A. CORPORATION OF NEW JERSEY.

. p srs'rnm or ELECTRICAL DISTRIBUTION.

Specification of Letters Patent. '4 I Patented Aug. 30 1921,

Application filed September' 19, 1919. Serial No. 325,003.

To all lwho/m, t many concern.'

Be it known that I, LEONARD A. WATSON, a citizen of the United States, residin at Bfroklyn in the county of'Kings and tate o ew such as will enable others skilled 1in the art to which it appertains to make and use the same. y

.This invention relates to systems of electrical distribution, and is more particularly directed to an improved railway car lighting system including an axle-driven generator and a battery adapted for connection to be charged thereby, and lamps adapted for connection to be supplied by the generator or by the battery and electro-responsive regulating means for the generator governed in accordance with the condition of the battery current.

It is one of the objects of the invention to provide a simplified and improved system of the character mentioned wherein the generator regulator, during effectiveness, acts with a tendency to malntain relative con-- stancy of generator voltage (as against speed changes and as against changes in the state of battery charge) at one of a plu'- rality of voltage values determined by means responsive to battery charging current and relatively indicative of the state of battery char e.

A urther object is to provide an improved system of the character mentioned which possesses features ofA structural superiority and functional advantage.

Other objects and advantages will be in part noted hereinafter in connection with the following description of the accom anying drawing, which lllustrates a typica but preferred, embodiment of the' invention and wherein is represented a simplified wiring dia am showing the electrical connections of t e various elements employed.

In general, there is represented an axledriven variable speed generator G having a shunt field winding F, which latter has in series therewith a variable4 regulating resistance, such .as a carbon p ile C1 The generator is adapted for connection by lines l and. 2

ork, have invented certain new- -and useful Improvements in Systems of Electrical Distribution, of which the following is a full, clear, and exact description,

'rent on account of the rising C'. E.

\with a storage battery B and lam L. A

wellknown form of main switch may be provided 1n line l to controlthe ycontinuity thereof in accordance with the action of la current coil 3 and a voltage coil 4 so designed as to connect the generator with ,the translatlng devices when and while the voltage of the generatorexceeds a predetermined value and to disconnect the generator when such voltage passes below a predetermined value. A lamp switch LS maybe provided between the battery and lamps and individual switches for. the separate lamps may valso bev resent where desired. A lamp regulator L lincluding a variable resistance is also provided to govern the value of voltage` constancy applied to the lamps during the period o current delive to the latter from the generator or from t e battery.

The degree of compression of the carbon p1le C', and therefore the relative strength of the field winding F of the generator2 is controlled by a bell crank lever 5 havlng connected thereto a core 6, the position of which is governed by an electro-responsive voltage coil .7 connected across the lines l and 2 by leads 8 and 9. It has heretofore been proposed to regulate a generator connected to charge a battery, by a voltage coil acting to maintain jrelative constancy of generator voltage at one level during the entire period of battery charging. Defects, however, have resided 1n such proposed systems and have heretofore prevented the successful utilization thereof. One such defect has been that if the regulating coil is designed to maintain generator voltage constancy at a level high enough to insure a full battery charge, then, at the beginnin of char e,1or with a lowered counter E. F. of t ev battery, an objectionably excessive charging current is supplied to the battery;

whereas, if the regulating coil` is designed to maintain relative generator voltage con- `stancy at a value low enough to restrict the charging current toa depleted battery within desirable limits, then such voltage value has too rapidly tapered the chargrig 1:cur

the batteryas the charge progresses, and a complete battery charging 1s not effected.

To overcome the defects thus noted, among others, by the present invention the setting of the voltage regulating coil 7 1s established to maintain generator voltage constancy at a predetermined lower value when and while the counter E. M. F. of the battery 1s such that too high a charging current would be delivered at the value of voltage constancy desirable toward the end of charging to a normal battery, and the voltage regulating coil 7 is set to maintain generator voltage constancy at a higher redetermined value when the counter E. F'. of the battery itself affords a safeguard against an excessive charging current.. As shown, there 1s provided, in the lead 8, an'element of resistance 10 adapted for incluslon, under certam conditions, in series with the coil 7 for weakening the effectiveness of the latter and thereby raising the value of the generator voltage constancy maintained; andadapted, under other conditions, for excluslon from the circuit of the regulating coil to relatively strengthen the latter, and thereby decrease the value of generator voltage constancy maintained. Resistance 10 consequently is provided with a shunt 11 thereabout, including contacts 12 and 13, governed by a relay R. This relay is of a character whereby the switch element thereof is adapted to maintain its instant limit of position until acted upon by a relay overload coil 14 connected in series with battery branch lead l5 on the one hand, or by a relay coil 16 adapted for connection by lines 17 and 18 across the battery. Line 17 includes contacts 18 and 19 governed by a switch 20, the position of which, to open orclose the line 17, depends on the strength of an underload coil 21, also connected in series with the battery in lead 15.

With one design of the parts and connections outlined, the functional working of the system may be described brieiiy as follows: Assuming the train at rest or the voltage of the generator below a predetermined value so that the main switch MS is open, no charging current will be delivered to the battery and coil 21 (which may be set to drop the relay switch element 20 when, say, less than twenty amperes current is supplied to the battery), causes the closure of lead 17 across contacts 18 and 19, and effects the energization of the coil 16 of relay R so that the latter responds to break the circuit of the shunt 11 across contacts 12 and 13 and thereby includes resistance 10 in series with the regulating coil 7. The regulating coil is thus set in its weakened condition, whereby the re-building of the generator voltage on re-starting and acceleration of the train is expedited and the re-closure of the main switch MS therefor effected with a minimum delay. Upon such re-closure of the main switch a charging current will be delivered to the battery in an amount dependent on the condition of the latter; that is, its C. E. M. F. opposing the applied voltage of the generator which, at the instant setting of regulating coil 7, may be, say, forty volts. Assuming first that at this time the battery is in a depleted condition so that, at such higher generator voltage an excessive current inrush to the battery would tend to ensue, coil 2l lifts switch 20 to open the circuit of coil 16 and then coil 14 is strengthened (being designed as an overload coil and set to actuate relay R upon the passage of, say, sixty amperes charging current) and responds to eifectclosure of the shunt 11 across contacts 12 and 13 and exclude resistance 10 from the circuit of the regulating coil 7, whereby the regulator is again set to maintain constancyof generator voltage at a predetermined lower level, say thirty-five volts, at which a charging current is supplied below that necessary to effectively energize coil 14: and above that necessary to permit coil 21 to release the switch element 20. This condition will obtain until the battery charge has ro ressed suiiiciently to raise the counter F of the battery with an attendant tapering of the charging current until the latter passes below the value for which the coil 21 is set, whereupon switch element 20 completes the circuit of the coil 16 and the relay R responds to re-include the resistance 10 in series with regulating coil 7 and the regulator thereafter acts, during the continuance of charging, to maintain relative constancy of generator voltage at a higher level, say forty volts, which insures the adequate completion of the battery charging without, however, entailing an injurious overcharge to a normal battery. Assuming, second, that at the time main switch MS is open and the resistance 10 consequently damping the effect of coil 7, the battery is in a major state of charge; then, on a resumption of generator effectiveness and re-closure of the main switch, the generator voltage maintained at say forty volts is correct, since the then condition of the counter E. M. F. of the battery affords its inherent protection against too heavy inrush, the coil 14 remains idle, and the regulation is continued unchanged at the higher level of voltage constancy with the battery current gradually tapering to afford its inherent protection against overcharge.

It will be observed that the regulation is at all times effected solely by the voltage coil 7 and the setting of the latter is governed in accordance with the needs of the system; and it .is to be understood that certain features of the invention are susceptible of modification and combination with attendant advantages of the present invention and without departure from the scope of the appended claims.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

l. In a car lighting system, in combination, a variable speed generator, a battery adapted'for connection to be charged thereby, a regulator for said generator including a voltage responsive coil connected across the generator mains, an element of fixed resistance in series with said coil, and automatic means responsive to battery chargingr current and operable upon the deliverance of said current in excess of a predetermined amountH to shunt said resistance and operable upon the deliverance of battery charging current less than a predetermined lower amount to open the shunt about said resistance.

2. In combination, a variable speed generator, a batteryv adapted for connection to be charged thereby, a. regulator for said generator including a voltage responsive coil connected across the generator mains and effective to maintain relative constancy of y generator voltage as agalnst speed changes and as against changes in the state of battery charge, and automatic means including a current overload coil and a current underload coil acting to affect said regulator for lowering the value of voltage constancy maintained thereby and for raising the value of voltage constancy maintained thereby upon the deliverance of charging current respectively above a predetermined high value and below a predetermined low value;

3.4 In combination, a variable speed generator, a battery adapted for connection to be charged thereby,a regulator for the generator comprising electro-responsive means to maintain relative 'constancy of generator voltage as against speed changes and as against changes in the state of battery charge at all times, and a controller for said electro-responsive means comprising a' series coil in the battery branch operative to ar"- fect said electro-responsive means to insure the maintenance by the latter of generator voltage constancy at a relatively lower value under certain conditions, and a series coil 1n the battery branch to affect said electroresponsive means for insuring the maintenance of generator voltage by the latter at a relatively high value under other conditions.

t. In combination, a variable speed gen-v erator, a storage battery adapted Jfor connection to be charged thereby, a regulator comprising a voltage responsive coil connected across the generator mains and tending whenel'ective to maintain relative constancy of generator voltage as against speed changes and as against changes in the state of battery charge, a resistance adapted for inclusion in the circuit of said coil to raise l the value of voltage constancy maintained thereby and for exclusion from said circuit to depress the value of voltage constancy maintained thereby, a current overload coil in the battery bran-ch acting upon the deliverance of charging current above a predetermined relatively high value to effect the exclusion of said resistance from the circuit of said coil, and a current underload coil in the battery branch acting upon the deliverance of charging current less than a predetermined relatively lower value to efect the inclusion of said resistance in the circuit of said coil.

5. In combination, a variable speed gener ator, a battery adapted for connection to be charged thereby, a regulator for said generator comprising a voltage responsive coil connected across the generator mains and acting to maintain relative constancy of generator voltage as against speed changes and as against changes in the state of battery charge, automatic electro-responsive means to insure the maintenance of a relatively low value of generator voltage constancy by said coil durin the periods oi relatively low counter E. F. of the battery and to insure the maintenance of'a relatively high generator voltage constancy by Said coil during periods of relatively high counter E. M. F. of said battery and to insure a minimum opposition of said coil tothe increase of generator voltage from zero to a predetermined value.

In testimony whereof I aliix my signature, in the presence of two witnesses.

LEONARD A. WATSON.

Witnesses:

HELEN M. SEAMANS, DAVID A. WooDcooK. 

